光学学报, 2019, 39(4): 0403001, 网络出版: 2019-05-10

基于电子散斑干涉与数字剪切散斑干涉法的悬臂薄板振动分析

Cantilevered Plate Vibration Analysis Based on Electronic Speckle Pattern Interferometry and Digital Shearing Speckle Pattern Interferometry
作者单位

1东南大学江苏省工程力学重点实验室, 江苏 南京 211189

2山东理工大学交通与车辆工程学院, 山东 淄博 255049

摘要
基于激光光路的光波随机相位扰动,分析了电子散斑干涉实时图像相减时模态条纹图的形成机理,提出了一种振幅涨落测量法。搭建了用于离面振动分析的电子散斑干涉和数字剪切散斑干涉测量系统,并对完整和含狭缝的悬臂铝板的振动特性进行了实验研究。实验结果表明,实时图像相减模式获得的模态条纹图对比度明显优于其他方法,得到的前10阶模态条纹图与有限元法计算结果具有良好的一致性。相比于电子散斑干涉法,数字剪切散斑干涉法对试样局部的刚度变化和缺陷更敏感。
Abstract
Based on the random phase perturbation of light waves in laser optical paths, the formation mechanism of mode fringe patterns is analyzed in the real-time image subtraction using an electronic speckle pattern interferometry (ESPI). An amplitude-fluctuation measurement method is proposed. The systems of ESPI and digital shearing speckle pattern interferometry (DSSPI) are established and used for the out-of-plane vibration analysis. In addition, the vibration properties of the intact and the cracked cantilever aluminum plates are investigated experimentally. The experimental results show that the visibility of mode fringe patterns obtained in the real-time image subtraction mode is obviously superior to those by the other methods. The obtained first 10 orders of modal fringe patterns are well consistent with the calculation results by the finite element method. Compared with ESPI, DSSPI is more sensitive to the local stiffness variation and flaws of specimens.
00 11